As the method of producing the TAIC, there are known a sodium cyanate method in which allyl chloride and sodium cyanate are reacted to obtain allyl isocyanate, and then the thus obtained allyl isocyanate is subjected to trimerization (Patent Document 1); and an isocyanuric acid method in which allyl chloride and isocyanuric acid (a tautomer of cyanuric acid) are reacted in the presence of a base catalyst (Patent Document 2).
TAIC is useful as a crosslinking agent having excellent heat resistance and chemical resistance, and it is expected to use TAIC in extensive applications such as electronic materials, liquid crystals, semiconductors and solar cells. For example, in printed circuit boards, i.e., plate- or film-shaped members constituting electronic circuits in which a number of electronic parts such as integrated circuits, resistors and capacitors are fixed on a surface thereof, and connected to each other through wirings, there is proposed the method in which TAIC is used as a sealing material for preventing penetration of substances such as liquids and gases into the respective electronic parts (Patent Document 3). In such a proposed method, TAIC is used as a liquid sealing material because the TAIC is present in the form of a viscous liquid (melting point: 26° C.) at an ordinary temperature. In addition, in order to enhance a wettability of TAIC, a silane coupling agent is added thereto. Also, TAIC is used as a crosslinking agent for crosslinkable polymers (Patent Document 4).
Meanwhile, although there is no report for impurities included in TAIC obtained by the above rearrangement of TAC, the impurities which may cause metal corrosion must be removed from TAIC to reduce their content to as small a level as possible.